Cough: COVID-19, flu, cold, RSV, or allergies – how to tell difference?

Overview

During the winter and early spring in Australia, coughs frequently occur due to various viruses and allergies. COVID-19, the flu, colds, RSV, and allergies can exhibit similar symptoms, which may lead to confusion. Knowing the distinct characteristics of each can help you determine whether to rest, get tested, or consult a GP. For immediate assistance, online services such as Hola Health can be beneficial.

COVID-19 vs flu vs cold vs RSV vs allergies

COVID-19 cough symptoms

COVID-19 coughs are often dry, persistent, and can make breathing feel uncomfortable. Other symptoms include:

• Fever
• Fatigue and body aches
• Loss of taste or smell (less common now)
• Sore throat or runny nose

When it is common in Australia

COVID-19 is present throughout the year and can surge at any time.

When to see a GP:

See a GP if:

• You have trouble breathing
• You’re older, pregnant, or have chronic conditions
• Your symptoms are severe or worsening

Flu (influenza) cough symptoms

Flu-related coughs can be dry or filled with mucus and often cause sharp or uncomfortable chest irritation.

Other common symptoms include:

• Sudden high fever
• Body aches and chills
• Extreme tiredness

When it is common in Australia

Flu cases peak during winter (June–September).

Cold cough symptoms

Cough features:

• Usually mild
• Dry or slightly wet
• Often appears later in the illness

Other symptoms:

• Runny nose
• Sneezing
• Sore throat

Australian note:

Colds occur year-round in Australia but are more common during winter.

RSV cough symptoms

In adults:

RSV symptoms in adults are usually mild but can be more severe in older individuals.

• Dry or wet cough
• Fatigue
• Congestion
• More common in older adults

In children:

RSV can be more serious in children, especially infants.

• Barky or wheezy cough
• Breathing difficulty
• Poor feeding (babies)

Australian context:

RSV activity has increased across Australia in recent years.

• RSV has been increasing in recent years, especially in the winter and spring seasons

Allergy cough symptoms

Cough features:

Allergy-related coughs are caused by irritation rather than infection.

• Dry, tickly
• Caused by throat irritation, not infection

Other symptoms:

• Sneezing
• Itchy eyes
• Runny or blocked nose
• No fever

Common Australian allergens:

• Spring pollen
• House dust mites
• Mould
• Grass and bushfire smoke irritation (common in summer)

How to tell which illness you have

Symptom breakdown

1. If you have a fever:

Fever is usually linked to viral infections rather than allergies.

• Likely COVID-19, flu, or RSV
• Not allergies

2. If you have itchy eyes:

This symptom strongly points to allergies.

• Likely allergies

3. If symptoms start suddenly:

Sudden onset is a hallmark of influenza.

• Mostly it is the flu

4. If cough persists after infection:

Lingering coughs are common after viral illnesses.

• Could be a post-viral cough from COVID-19, a cold, or RSV

5. If wheezing is present:

Wheezing suggests airway involvement.

• Possibly RSV, asthma flare, or allergies

6. If many people around you are sick:

Widespread illness usually points to a contagious virus.

• Likely a viral illness

When to see a GP or get tested

Seek medical advice if you experience any of the following:

• Shortness of breath
• Persistent cough lasting more than 2–3 weeks
• High fever
• Chest pain
• Pregnancy or a compromised immune system
• Uncertainty between COVID-19 and the flu
• RSV concerns in babies or the elderly

How Hola Health can help

Hola Health provides convenient access to medical care for respiratory symptoms.

• Online GP assessment for cough symptoms
• Prescriptions (antivirals, inhalers, allergy medications)
• Medical certificates if illness impacts work
• Advice on testing (COVID-19, flu, or RSV)
• Follow-up care if symptoms worsen

FAQs

Is a dry cough always COVID-19?

No. Flu, RSV, colds, and allergies can all cause dry coughs.

How long does a post-viral cough last?

A post-viral cough can last anywhere from 2–6 weeks, depending on the virus.

Can allergies cause a cough without congestion?

Yes, throat irritation can cause a tickly cough even without nasal symptoms.

How do I know if I need a COVID-19 test?

If you have a fever, a new cough, a sore throat, or have been around someone with COVID-19, testing is recommended.

Are RSV and flu dangerous for adults?

Yes. While often mild, both can be serious in older adults or people with chronic health conditions.

Recognising the right time to seek medical attention is essential to prevent complications. While mild symptoms usually improve with home care, seek medical review for severe, persistent, or worsening symptoms to receive an accurate diagnosis and appropriate treatment.